1. Field of the Invention
This invention relates to sheets mitigating vibration and impact noises, and more particularly to impact-cushioning sheets for use in vessels housing damageable objects, protective members for precision instruments, casings requiring vibration damping performane, covering members for piping such as ducts or the like, base members for precision instruments, damping member for audio related articles, floor damping members for buildings, vibration damping and heat insulating members, vibration damping members for vehicles and vessels, deadening members for preventing transmission of electromagnetic waves, deadening members for preventing occurrence of static electricity and the like. Furthermore, it relates to floor damping structures for direct application using such an impact-cushioning sheet.
2. Related Art Statement
Recently, the technical advance with respect to this type of impact-cushioning sheet is remarkable, and various developments having been attempted. Particularly, the attempts for preventing vibrations take large expenditures because of technical difficulties, so that it is long-awaited to develop means for preventing vibrations at low cost. That is, although the demand for preventing vibrations is relatively tolerant in the past, it is strongly demanded to provide more quiet space in machines and instruments disliking vibrations as well as buildings, vehicles and vessels with the recent high-grade trend.
Especially, it is said that the remaining subject matter in the building field is narrowed down to two points of dropwise condensation and vibration noise at the present. Lately, various countermeasures for the problem of vibration noise are taken in various places, but there are still many fields not providing a sufficient effect for the prevention of vibration noises because of technical difficulties. For example, such fields include the building field using floor members. Particularly, various studies with respect to the floor member have been made, but floor members developing good noise controlling performances are not yet obtained up to date.
As to the floor member, residents demanding the use of a woody floor member are increasing because the woody floor members have some merits such that the cleanliness is held, and the living of mildews and harmful insects such as acari, and so on, is difficult, and the color tone is sober. However, the woody floor member has only a demerit that floor impact sounds such as walking sounds, falling sounds and the like can not completely be mitigated, so that the use of a woody floor member as an upstairs floor is unfavorable considering annoyances to downstairs residents.
Therefore, it is strongly demanded to develop floor members having an improved sound deadening performance.